Page 1201 of 3115
A21041
32 1 4 5
-20 0 20 40 60 80 100 0.1 0.2 0.3 0.51 2 3 5 10 20 30
TEMPERATUREC(F)
RESISTANCE kW
(-4) (32) (68) (140)(104) (212)(176)
Air
VG
E2G+B
THA E2
Acceptable
DI-152
- DIAGNOSTICSENGINE
345 Author: Date:
2004 LAND CRUISER (RM1071U)
4 Check mass air flow meter.
PREPARATION:
Remove the mass air flow meter.
CHECK:
(a) Inspect output voltage.
(1) Apply battery voltage across terminals +B and E2G.
(2) Connect the positive (+) tester prove to terminal VG,
and negative (-) tester prove to terminal E2G.
(3) Blow air into the mass air flow sensor, and check
that the voltage fluctuates.
(b) Inspect resistance.
(1) Measure the resistance between terminals of the in-
take air temperature sensor.
Resistance:
Tester ConnectionTemperatureSpecified Condition
-20C (-4F)13.6 to 18.4 kW
THA (4) - E2 (5)20C (68F)2.21 to 2.69 kWTHA (4) E2 (5)
60C (140F)0.49 to 0.67 kW
NG Replace mass air flow meter.
OK
Page 1202 of 3115

S01196S01699
30
20
10
5
3
02040 0.11
0.3
0.2 0.52
60 80 100 -20
(-4) (104) (140) (176)(32) (68) (212)
A21042
Ohmmeter
Acceptable
TEMPERATURE C (F)
RESISTANCE KW
- DIAGNOSTICSENGINE
DI-153
346 Author: Date:
2004 LAND CRUISER (RM1071U)
5 Check engine coolant temperature sensor.
PREPARATION:
Remove the engine coolant temperature sensor.
CHECK:
(a) Measure the resistance between the terminals of the en-
gine coolant temperature sensor.
Resistance:
Tester ConnectionSpecified Condition
122.32 to 2.59 kW (20C (68F))1 - 20.310 to 0.326 kW (80C (176F))
NOTICE:
In case of checking the engine coolant temperature sensor
in the water, be careful not to allow water to go into the ter-
minals. After checking, dry the sensor.
HINT:
Alternate procedure: Connect an ohmmeter to the installed en-
gine coolant temperature sensor and read the resistance. Use
an infrared thermometer to measure the engine temperature in
the immediate vicinity of the sensor. Compare these values to
the resistance/temperature graph. Change the engine temper-
ature (warm up or allow to cool down) and repeat the test.
(b) Reinstall the engine coolant temperature sensor.
NG Repair or replace engine coolant temperature
sensor.
OK
6 Check for spark and ignition (See page IG-1).
NG Repair or replace ignition system.
OK
Page 1203 of 3115
DI-154
- DIAGNOSTICSENGINE
347 Author: Date:
2004 LAND CRUISER (RM1071U)
7 Check fuel pressure (See page SF-7).
CHECK:
Check the fuel pressure (high or low pressure).
NG Check and replace fuel pump, pressure regula-
tor, fuel pipe line and filter (See page SF-1).
OK
8 Check exhaust system for gas leakage.
NG Repair or replace exhaust gas leakage point.
OK
Page 1204 of 3115
Q30018
- DIAGNOSTICSENGINE
DI-155
348 Author: Date:
2004 LAND CRUISER (RM1071U)
9 Check output voltage of heated oxygen sensor (bank 1, 2 sensor 1) during id-
ling.
PREPARATION:
(a) Warm up the heated oxygen sensor with the engine speed at 2,500 rpm for approximately 90 seconds.
(b) Connect the hand-held tester or OBD II scan tool to the DLC3.
(c) When using hand-held tester, enter the following menu: DIAGNOSIS / ENHANCED OBD II / DATA
LIST / ALL / O2S B1 S1 or B2 S1.
CHECK:
Check the output voltage of the heated oxygen sensor during idling using the OBD II scan tool or hand-held
tester.
OK:
Heated oxygen sensor output voltage:
Alternates between less than 0.4 V and more than 0.55 V (See the following table).
.
OK Go to step 17.
NG
Page 1205 of 3115
A20870
E1 +B
OX
+BHT
OX E1HT H5
H7
H6
H8
Components Side:
Bank1 Sensor1, Bank2 Sensor1
Bank1 Sensor2, Bank2 Sensor2
A21543
1
23
4 EFI or ECD Relay
DI-156
- DIAGNOSTICSENGINE
349 Author: Date:
2004 LAND CRUISER (RM1071U)
10 Check resistance of heated oxygen sensor heater.
PREPARATION:
Disconnect the H5, H6, H7 or H8 heated oxygen sensor con-
nector.
CHECK:
Measure resistance between terminals of the heated oxygen
sensor.
OK:
Tester ConnectionSpecified Condition
HT (H5-1) - +B (H5-2)11 to 16 W (20°C)
HT (H6-1) - +B (H6-2)11 to 16 W (20°C)
HT (H7-1) - +B (H7-2)11 to 16 W (20°C)
HT (H8-1) - +B (H8-2)11 to 16 W (20°C)
NG Replace heated oxygen sensor.
OK
11 Check EFI or ECD relay.
PREPARATION:
Remove the EFI or ECD relay from the engine room R/B.
CHECK:
Inspect the EFI or ECD relay.
OK:
Terminal No.ConditionSpecified Condition
2 - 4ConstantContinuity
UsuallyNo Continuity
1 - 3Apply B+ between
terminals 2 and 4Continuity
NG Replace EFI or ECD relay.
OK
Page 1206 of 3115

A20870
E1 +B
OX
+BHT
OX E1HT H5
H7
H6
H8
Components Side:
Bank1 Sensor1, Bank2 Sensor1
Bank1 Sensor2, Bank2 Sensor2
A21340ECM Connector HT1BHT1AOX1A
OX2A
HT2B
HT2AOX1B E6
OX2B
- DIAGNOSTICSENGINE
DI-157
350 Author: Date:
2004 LAND CRUISER (RM1071U)
12 Check for open and short in harness and connector between ECM and heated
oxygen sensor.
PREPARATION:
(a) Disconnect the H5, H6, H7 or H8 heated oxygen sensor
connector.
(b) Disconnect the E6 ECM connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
OX (H5-3) - OX1A (E6-23)Below 1 W
HT (H5-1) - HT1A (E6-4)Below 1 W
OX (H6-3) - OX1B (E6-29)Below 1 W
HT (H6-1) - HT1B (E6-5)Below 1 W
OX (H7-3) - OX2A (E6-22)Below 1 W
HT (H7-1) - HT2A (E6-33)Below 1 W
OX (H8-3) - OX2B (E6-21)Below 1 W
HT (H8-1) - HT2B (E6-25)Below 1 W
OX (H5-3) or OX1A (E6-23) -
Body ground10 kW or higher
HT (H5-1) or HT1A (E6-4) -
Body ground10 kW or higher
OX (H6-3) or OX1B (E6-29) -
Body ground10 kW or higher
HT (H6-1) or HT1B (E6-5) -
Body ground10 kW or higher
OX (H7-3) or OX2A (E6-22) -
Body ground10 kW or higher
HT (H7-1) or HT2A (E6-33) -
Body ground10 kW or higher
OX (H8-3) or OX2B (E6-21) -
Body ground10 kW or higher
HT (H8-1) or HT2B (E6-25) -
Body ground10 kW or higher
Page 1207 of 3115
A21040
Reference (Bank 1 Sensor 1 System Drawing)
From
BatteryEFI or ECD
No. 1 FuseEFI or ECD
RelayEFI or ECD
No. 2 FuseHeater Oxygen
Sensor
Heater
SensorHT1A
OX1A
E2
MRELECM
DI-158
- DIAGNOSTICSENGINE
351 Author: Date:
2004 LAND CRUISER (RM1071U)
NG Replace or replace harness or connector.
OK
13 Replace heated oxygen sensor.
Go
Page 1208 of 3115

A09299A21418
Vehicle speed
(30 km/h)19 mph
IG SW OFF
Warm up
2 minutes 2 minutes 2 minutes
(1)(3)
(4)
Idling(2)(3)
(4)(3) 3 to 5 minutes 3 to 5 minutes 3 to 5 minutes
(4)
- DIAGNOSTICSENGINE
DI-159
352 Author: Date:
2004 LAND CRUISER (RM1071U)
14 Perform confirmation driving pattern.
(a) Disconnect the battery terminal and wait for a minute (clear learning value of the air fuel ratio). (1)
(b) Connect the hand-held tester to the DLC3. (1)
(c) Switch the hand-held tester from the normal mode to the check mode (See page DI-3). (1)
(d) Start the engine and let it idle until engine coolant temperature is 75 °C (167 °F ) or more. (2)
(e) Drive the vehicle at 19 mph (30 km/h) or more for 3 minutes or more. (3)
(f) Let the engine idle for approx. 2 minutes. (4)
(g) Perform steps (e) and (g) at least 3 times.
HINT:
If a malfunction exists, the MIL will be illuminated during step (f).
NOTICE:
If the conditions in this test are not strictly followed, detecting a malfunction may be difficult. If you
do not have a hand-held tester, turn the ignition switch OFF after performing steps (e) to (f), and then
do step (f) again.
GO
15 Is there DTC P0171, P0172, P0174 or P0175 being output again?
YES Replace ECM (See page SF-60) and perform
confirmation driving pattern (Refer to step 14).
NO